ATTINY861-20PU Atmel, ATTINY861-20PU Datasheet - Page 13

• Manufacturer Part Number: ATTINY861-20PU
• Description: Microcontrollers (MCU) 8kB Flash 0.512kB EEPROM 16 I/O Pins
• Manufacturer: Atmel

Specifications of ATTINY861-20PU

• Processor Series: ATTINY8x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: 2-Wire/SPI/USI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 2
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRMC320
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 11-ch x 10-bit
• Program Memory Type: Flash
• Program Memory Size: 8 KB
• Package / Case: PDIP-20
• Controller Family/series: AVR Tiny
• Core Size: 8 Bit
• No. Of I/o's: 16
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 20MHz
• No. Of Timers: 2
• Rohs Compliant: Yes
• Package: 20PDIP
• Device Core: AVR
• Family Name: ATtiny
• Maximum Speed: 20 MHz
• Ram Size: 512 Byte
• Operating Temperature: -40 to 85 °C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2588E–AVR–08/10
to be cleared. If an interrupt condition occurs while the corresponding interrupt enable bit is
cleared, the Interrupt Flag will be set and remembered until the interrupt is enabled, or the flag is
cleared by software. Similarly, if one or more interrupt conditions occur while the Global Interrupt
Enable bit is cleared, the corresponding Interrupt Flag(s) will be set and remembered until the
Global Interrupt Enable bit is set, and will then be executed by order of priority.
The second type of interrupts will trigger as long as the interrupt condition is present. These
interrupts do not necessarily have Interrupt Flags. If the interrupt condition disappears before the
interrupt is enabled, the interrupt will not be triggered.
When the AVR exits from an interrupt, it will always return to the main program and execute one
more instruction before any pending interrupt is served.
Note that the Status Register is not automatically stored when entering an interrupt routine, nor
restored when returning from an interrupt routine. This must be handled by software.
When using the CLI instruction to disable interrupts, the interrupts will be immediately disabled.
No interrupt will be executed after the CLI instruction, even if it occurs simultaneously with the
CLI instruction. The following example shows how this can be used to avoid interrupts during the
timed EEPROM write sequence.
Note:
When using the SEI instruction to enable interrupts, the instruction following SEI will be exe-
cuted before any pending interrupts, as shown in the following examples.
Assembly Code Example
C Code Example
Assembly Code Example
in r16, SREG
cli
sbi EECR, EEMPE
sbi EECR, EEPE
out SREG, r16
char cSREG;
cSREG = SREG; /* store SREG value */
/* disable interrupts during timed sequence */
_CLI();
EECR |= (1<<EEMPE); /* start EEPROM write */
EECR |= (1<<EEPE);
SREG = cSREG; /* restore SREG value (I-bit) */
sei
sleep
See
“Code Examples” on page
; disable interrupts during timed sequence
; set Global Interrupt Enable
; enter sleep, waiting for interrupt
; note: will enter sleep before any pending interrupt(s)
; store SREG value
; start EEPROM write
; restore SREG value (I-bit)
6.
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